Trypanosome Detection (Wet Film & Buffy Coat Smear)
Trypanosome detection is a microscope test that looks for tiny blood parasites, such as Trypanosoma evansi, which causes surra, in fresh blood and in a buffy coat smear made from spun blood. It is used for cows, buffaloes and dogs; a negative smear does not rule infection out.
- Sample
- Whole blood (EDTA)
- Quantity
- As advised
- Report
- Confirmed when you book
- Collection
- Free in Bhopal
What this test checks
- Moving trypanosomes seen in a drop of fresh blood (wet film)
- Trypanosomes gathered near the buffy coat after the blood is spun
- Signs of Trypanosoma evansi, the blood parasite that causes surra
Benefits of this test
- Can show the parasite itself, which supports a diagnosis of surra when it is found.
- Uses a simple EDTA blood sample from a cow, buffalo or dog.
- Helps your vet decide whether a PCR or an antibody test is needed.
- Can be repeated, which helps because parasites may be missed in a single sample.
- Can help your vet check other animals when surra is found in a herd.
Often discussed at these ages:Adult Horse
When your vet may advise it
- Fever that comes and goes, with dullness or weakness, in a cow, buffalo or dog.
- Weight loss, pale gums or inner eyelids, or a fall in milk yield without a clear cause.
- Swelling of the legs, chest, lower belly or face.
- Nervous signs such as circling or pressing the head against a wall, especially in buffaloes.
- Abortion in a cow or buffalo when your vet suspects a blood parasite.
- Another animal in the herd or nearby has been found with surra.
About this test
Trypanosomes are tiny parasites that swim in the blood. One of them, Trypanosoma evansi, causes surra, a disease seen in India in cows, buffaloes, dogs and some other animals. It is spread mainly by biting flies that carry blood from one animal to another. Infected animals may have fever that comes and goes, weakness, weight loss and anaemia, which means too few red blood cells. Some animals carry the parasite with few signs.
This test looks for the parasites under a microscope in two ways. In a wet film, a drop of fresh blood is checked for moving parasites. For a buffy coat smear, the blood is first spun in a thin tube. The parasites gather near the buffy coat, the thin pale layer of white cells that forms between the red cells and the liquid part of the blood, so this layer is checked closely. The sample is whole blood in an EDTA tube, which stops it from clotting, and it should reach the lab fresh.
Finding trypanosomes supports a diagnosis of surra. A negative smear does not rule infection out, because the parasites can be few and come and go from the blood. If your vet still suspects surra, they may repeat the smear or add a Trypanosoma evansi (Surra) PCR or antibody ELISA. PCR looks for the parasite's genetic material, and an antibody test shows whether the animal has been exposed to it. A registered veterinarian reads the result together with the animal's signs and history. When one animal in a herd has surra, your vet may also suggest checking the others.
How to prepare
Tell your vet when the fever started and about any medicines already given, and get the EDTA blood sample to the lab as fresh as possible. The lab confirms the method, sample needs and reporting time when you book.
Reading the result
A registered veterinarian reads the result together with the animal's signs, history and other tests. Seeing trypanosomes supports surra. A negative smear does not rule infection out, because the parasites can be few or absent from the blood for a while, so your vet may repeat the smear or add a PCR or antibody test.
Questions about Surra smear
What is surra disease in cows and buffaloes?
Can a negative blood smear rule out surra?
Can dogs get surra?
Why does the blood sample for a surra test need to be fresh?
Before you book this test
Why this notice: so you know, before you book, how a test is done, what its limits are and who is responsible.
- Where it is tested. Some tests are done wholly or partly by an independent partner laboratory. The lab tells you before booking if this test is sent out, and the report names the laboratory that did it.
- What a result can and cannot tell you. No test is right every time. A normal result does not rule out every disease, and an abnormal result does not prove one. A registered veterinarian should read the report with the animal’s signs and history before any treatment is started, changed or stopped.
- The sample. A sample that is clotted, too small, wrongly labelled, leaking or too old may be rejected or reported with a note, and the lab may ask for a fresh one.
- Reporting time. Confirmed when you book. Times are estimates, not guarantees, and the lab confirms the time when you book.
- Emergencies. A booking or a pending report must not delay urgent care. If an animal has collapsed, struggles to breathe, has fits or bleeds heavily, call a veterinarian at once.
Please read our Terms of Service, Medical Disclaimer, Privacy Policy and Refund and Cancellation Policy. Pashupatinath Vet Lab is operated by Duaji Healthcare and Tech Private Limited. This page is general information and does not replace a veterinarian’s advice.
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